Discharge lamp ballast assembly



June 14, 1949, J SHAHEEN DISCHARGE LAMP BALLAST ASSEMBLY Filed Aug.23,,1945

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ATTORN EY Patented June 14, 1949 DISCHARGE LAMP BALLAST ASSEMBLY JohnShaheen, West Roxbury, Mass, assignor to Sylvania Electric Products1110., Salem, Mass, a corporation of Massachusetts Application August23, 1945, Serial No. 612,274

1 Claim. 1

This invention relates to an electric discharge lamp ballast assemblyand more particularly to a supporting plate for assembling the parts ofa ballast and to the mounting thereon of a condenser and a plurality ofinductors.

An object of this invention is to provide a mounting for the parts of aballast, said mounting to save substantial weight.

Another object of this invention is to provide an open type ballast withsufiicient ventilation to eliminate external heat.

Another object of this invention is to provide a ballast readilyassembled and cheaper to produce commercially than ballasts heretoforeassembled.

A feature of this invention is that the ballast may be protected by theusual method of impregnation, said method of sealing and impregnatingthe ballast depending upon the use of the device and its location withrespect to the fixture. The ballast may be sealed as a solid mass andimpregnated with a resinous mixture or the parts may be coatedindividually, assembled, covered with a tarr substance and the entireballast covered with a metal casing. The latter method provides anexplosion-proof device which will stand the test of use outside anappliance in all kinds of atmosphere.

Another feature of this invention is the position of the condenseroutside the plurality of inductors, thus producing a device so muchcooler than ballasts previously assembled that smaller units may beused. Furthermore, the elimination of considerable heat in the ballastprevents any melting of the potting compound and leakage resultingtherefrom.

Other objects, advantages, and features of this invention will beapparent from the detailed description taken in conjunction with theaccompanying drawings, in which:

Figure 1 is a perspective view of the assembled ballast before beingimpregnated and sealed;

Figure 2 is a perspective view of the metal plate on which are mountedthe condenser at one end and the transformer and two reactors end to endon the inwardly projecting steps at the other end; and

Figure 3 is a cross-sectional view of the plate showing the troughthrough which the wires pass to the terminal attachments.

In Figure 1, the condenser l is mounted at one end of the supportingplate 2; the transformer 3 and the two reactors 4 are supported end toend on the inwardly projecting steps of the plate, thus allowing thelead wires to pass through the trough to the terminal plate 5. On theterminal plate 5, are mounted the pins 6 for wire attachments. On thesupporting plate are placed projecting tabs l for fitting over theprojecting. edges 8 of the condenser I, thus holding it firmly in place.9 and I ll represent slots in the supporting plate for attaching theballast to the fixture.

In Figure 2, the plate 2 is flanged longitudinally for holding thecondenser and inductors in place and is further designed with inwardlyprojecting steps II on which the inductors rest. In conjunction with thepart of the plate between the inwardly projecting steps ll the inductorsform a duct for the wires to pass to the terminal plate. Furthermore, atthe other end of the basic and supporting plate are the tabs 1 forholding the condenser firmly in place. At the ends of the supportingplate are the slots 9 and It! for attaching the ballast to the fixture.

In Figure 3, the tab 1 for holding the condenser is shown projectingfrom the plate. By resting on the inwardly projecting steps II, theinductors form a duct 12 for wires. The flanges l3 extend throughout thelength of the plate.

What I claim is:

A ballast assembly for electric discharge lamps, said ballast assemblycomprising: a unitary elongated metal supporting piece having its bottomportion substantially flat and having upwardly-extending longitudinalflange portions along substantially its entire length and having alongpart only of its length a pair of re-entrant steps, each step extendingupwardly from said bottom portion and inwardly from a flange portion, aplurality of inductors placed end to end and mounted between saidflanges and resting on said steps to form a duct, and a condenserextending between the flanges and fixed to the bottom of said metalpiece at the end of said pair of reentrant steps at the end of the duct.

JOHN SHAHEEN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,817,034 Hotchkin Aug. 4, 19312,109,725 Hart Mar. 1, 1938 2,145,546 Kingdom Jan. 31, 1939 2,158,868Stacy May 16, 1939 2,372,083 Johansson et a1. Mar. 20, 1945

